Our research goal is to understand precursor emissions, chemical processes, and transport that determine the global distributions of tropospheric ozone and aerosols, and to characterize the influence of global climate and chemical change on regional air quality and the effects of regional pollution on the global atmosphere. We work on global and regional 3-dimensional (3-D) modeling and analysis of satellite, aircraft, and ground observations. We use the GEOS-Chem global 3-D model of tropospheric chemistry-aerosols, the CMAQ regional air quality model driven by WRF, and the WRF-Chem model. A particular research focus is chemical data assimilation and inverse modeling using the aforementioned models and (in some cases) their adjoints. We work closely with satellite teams including TES, MLS, MISR, AIRS, MOPITT, MODIS, SCIAMACHY, and OMI, among others. We have close collaborations with satellite instrument teams at the Jet Propulsion Laboratory. The group leader is Prof. Qinbin Li. There are currently position openings for undergraduate and graduate students as well as postdocs.

reports on our study of detecting and analyzing CO2 from space. “Although originally designed to measure atmospheric water vapor and temperature profiles for weather forecasting, data from the Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua spacecraft are now also being used by scientists to observe atmospheric carbon dioxide. Scientists from NASA; the National Oceanic and Atmospheric Administration; the European Center for Medium-Range Weather Forecasts; the University of Maryland, Baltimore County; Princeton University, Princeton, New Jersey; and the California Institute of Technology (Caltech), Pasadena, Calif., are using several different methods to measure the concentration of carbon dioxide in the mid-troposphere (about eight kilometers, or five miles, above the surface). The global map of mid-troposphere carbon dioxide above, produced by AIRS Team Leader Dr. Moustafa Chahine at JPL, shows that despite the high degree of mixing that occurs with carbon dioxide, the regional patterns of atmospheric sources and sinks are still apparent in mid-troposphere carbon dioxide concentrations. "This pattern of high carbon dioxide in the Northern Hemisphere (North America, Atlantic Ocean, and Central Asia) is consistent with model predictions," said Chahine. Climate modelers, such as Dr. Qinbin Li at UCLA and JPL, and Dr. Yuk Yung at Caltech, are currently using the AIRS data to study the global distribution and transport of carbon dioxide and to improve their models.”